Tubular-rivet cap.



Patented Mar. H, I902.

W P BARTEL TUBULAR BiVET CAP.

(Application filed Dec. 6, 1901 (No Model.)

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\VILLIAM P. BARTEL, OF \VALTIIAM, MASSACHUSETTS, ASSIGNOR TO J UDSON L.THOMSON MANUFACTURING COMPANY, OF IVALTHAM, MASSACHUSETTS, A CORPORATIONOF MAINE.

TUBULAR-'RIVET CAP.

SPECIFICATION forming part of Letters Patent No. 695,265, dated March11, 1902. Application filed December 6, 1901. Serial No. 84,916. (Nomodel.)

To all whom it may concern:

Be it known that I, WILLIAM P. BARTEL, a citizen of the United States,residing at Waltham, in the county of Middlesex and State ofMassachusetts, have invented new and useful Improvements inTubular-Rivet Caps, of which the following is a specification.

The object of this invention is to provide a cap for a tubular rivet,said cap being so constructed as to assist in the splitting of thetubular portion of said rivet at the end thereof and also in theclenching of said rivet in said cap when the rivet is driven thereon.

The invention consists in a cap for a tubular rivet having a pyramidalspreader.

Referring to the drawings, Figure 1 is a perspective view of my improvedtubular-rivet cap. Fig. 2 is a plan view of the same. Fig. 3 is asection taken on line 3 3 of Fig. 2. Fig. 4 is a section taken on line 44 of Fig. 2. Fig.

5 is a diagrammatic horizontal section taken on line 5 5 of Fig. 3,showing in connection therewith the shank of a tubular rivet as itappears when first coming in contact with the cutting edges of thepyramidal spreader. Fig. 6 is a view similar to Fig. 5, showing thesections of the shank of the tubular rivet as it appears after havingbeen driven upon the pyramidal spreader. Fig. 7 is a sectional elevationshowing a tubular rivet clenched to a cap, having a spreader constructedin accordance with my invention and said cap and rivet being showndriven into two pieces of material. Fig. Sis a plan view of a cap havinga hexagonal spreader therein.

Like numerals refer to like parts throughout the several views of thedrawings.

In the drawings, 10 is a tubular-rivet cap constructed in accordancewith my invention. Said cap is formed from a circular disk of sheetmetal by means of dies, the rim 11 there of being turned over to form anannular recess 12, and the central portion being struck up to form apyramidal spreader 13. The spreader 13, as shown in Figs. 1 and 2, hasfour faces 14 14, the intersection of each of two adjacent faces formingcutting edges 15 15.

The tubular rivet 16, Fig. 7, is driven through the stock in the usualmanner, the

end of the tubular shank of the rivet first coming' into contact withthe cutting edges of the pyramidal spreader 13, as shown in Fig. 5. Uponpressing the rivet downwardly upon the spreader the cylindrical shape ofthe shank portion in contact with said spreader assumes, approximately,the form of a square, and then is divided by the cutting edges 15 15into four parts, 17 17, Fig. 6. Upon a further pressure upon the rivetthese parts divide and curl outwardly and upwardlyinto the annularrecess 12, as shown in Fig. 7. It will be seen that during this latterportion of the clenching operation of the rivet to the cap the faces 1414 perform an important function, as well as the cutting edges 15 15,said faces 14 14 forming a continuous surface against which each of theparts 17 bears as the rivet is being forced upon the cap, or vice versa,bending the divided parts 17 17 and guiding them outwardly to enter saidrecess 12.

It will be seen that in addition to splitting the shank of the rivet andspreading the divided-portions thereof to enter the annular recess 12,as hereinbefore set forth, the shape of the spreaderin horizontalcross-section, as

shown in Figs. 5 and 6, prevents the cap from turning upon the rivet.

While I prefer to use a rivet having a pyramidal spreader with fourfaces, it is evident that the number of said faces may be varied withoutdeparting from the spirit of my invention.

It is evident that the faces 14 14 may be formed slightly convex orconcave without departing from the spirit of my invention.

Having thus described my invention, what I claim, and desire by LettersPatent to secure, is.

A cap for a tubular rivet having a pyramidal spreader, substantially asdescribed.

In testimony whereof I have hereunto set my hand in presence of twosubscribing witnesses.

WILLIAM P. BARTEL.

I/Vitnesses:

CHARLES S. Goonme, ANNIE J. DAILEY.

